Abstract:

The purpose of the study was to analyse traffic safety in different traffic environments based on the features of public roads and related environment. The data on personal injury accidents in 2001-2010 was utilized in the empirical part of the study. Traffic safety in the 21st century was presented as a multi-dimensional issue that includes the following main elements: exposure, risk, and severity. In addition, the factors affecting traffic safety were described. A major part of annual personal injury accidents (average 3 495 accidents per year) took place in rural areas. 32% of these accidents occurred on two-lane main roads, while 40% occurred on roads with lower classification. Fifteen per cent of personal injury accidents occurred in areas marked with built-up area signs and 13% on motorways and other divided highways. In comparison to personal injury accidents, the fatalities (267 fatalities per year) concentrated more on undivided main roads in rural areas (44% of all fatalities). In the 21st century, the number of fatalities has decreased by 18% on ordinary main roads in rural areas. On other roads this kind of trend does not exist.

Head-on collisions were the most severe problem on undivided roads in rural areas. Considering the roads in areas marked with built-up area signs, the most severe problems were accidents to pedestrians and cyclists, especially in regard to mopeds. In motorways, most problems were related to single-vehicle accidents and rear-end accidents. However, the fatality risk was smallest on motorways and other divided highways and on roads with median barriers. There was no significant difference in fatality risks between other road types. Regional traffic safety was scrutinized by comparing the number of personal injury accidents and fatalities.

The infrastructural differences between regions (regions were based on governance areas listed by the Centres for Economic Development, Transport and the Environment) were differentiated from traffic safety aspects. This should facilitate the development of more efficient ways to improve traffic safety in specific areas. The traffic safety of the links on the main road network was studied by comparing the accident data of those links with data of other similar roads, and by estimating accident and fatality risks via developed algorithms.

As head-on collisions were the most severe safety problem on public roads, it seems that installing median barriers on roads with heavy traffic is the most efficient long-term measure. Also the use of motor-traffic ways without median barriers should be actively reduced. Based on the results, it is not recommended to build extra-wide roads without median barriers, as their safety impact is minor or even negative. Based on the results of the regional risk analysis, it is recommended to execute measures improving traffic safety at regional level. Finally, the fastest way to reduce the number of fatalities is to increase automated speed surveillance, especially on busy roads with a high density of road fatalitiesMaanteiden turvallisuutta tarkasteltiin eri liikenneympäristöissä tien ja tieympäristön ominaisuuksien näkökulmasta. Työssä käytettiin aineistona henkilövahinkoon johtaneita onnettomuuksia vuosilta 2001-2010. Tarkastelussa pyrittiin hahmottamaan 2000-luvun turvallisuustilannetta moniulotteisena kokonaisuutena, jonka pääelementit ovat altistus, riski ja vakavuus ja löytämään vaikuttavia tekijöitä turvallisuuden taustalla.